2002 Jag S type V6

Friend just picked up a mint low mileage S type 3.0, 2002 with 106000km on the clock. It needs brakes, but before getting into that
it has another issue. It starts perfectly, then after a few seconds of running the CEL flashes, it runs rough, and gives message it is running at reduced power. Code P0300 comes up. Is this likely to be a cam sensor problem? (disconnecting both makes NO difference - which makes me suspicious) or a fuel pressure problem? (is there a schrader valve on an 02 where I can connect the pressure tester - if so where?)
I've done some work on old Jags - e types and MkIIs and old XJs - but out of the loop on the new high-tech Jags. Looks a lot like (my old) Mystique 2.5 and Taurus 3.0 18 valve engines but totally different ignition and fuel systems.
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Hello,
I don't have a suggestion for the repair but have a hint.
There is a website/forum for the Ford/Lincoln LS, which is basically the same as the Jaguar S-Type. Sheet metal is different but it appears the engine, drivetrain, suspension and most everything else is all Jag.
https://www.lincolnvscadillac.com/forum/forums/lincoln-ls.7/
There is also a section for servicing, including some manuals.
I beleive yours would be the same as a Gen 1, six cylinder.
There are a few regulars on there that seem to eat, drink and know pretty much everything to know about the LS. They may be able to suggest a starting point.
I don't want to mislead you but the fuel pump is a likely suspect, I've seen enough posts about replacing it where it looks like it's something that doesn't last the life of the rest of the car.
Good luck.
-bruce snipped-for-privacy@ripco.com
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